1. Field of the Invention
The present invention relates to a recording apparatus using a stepping motor and, more particularly, to a recording apparatus which uses a stepping motor in an optimal state.
2. Related Background Art
Conventionally, the print speed and consumption power are determined by several ways of predetermined setting. As for the print speed, for example, an ink-jet recording apparatus has print modes such as a high-quality mode that realizes normal print quality, a high-speed mode that realizes high-speed printing, a super-high quality mode that realizes highest quality, and the like, and the carriage is driven at different speeds in these modes. The speed is normally determined and set based on the relationship among the ink ejection frequency, the power of the motor to be used, and the weight of the carriage. As for consumption power, a means for suppressing consumption power during a print standby state or the like is used.
As for the motor to be used, in an image-quality priority model, a DC motor is driven by closed-loop control using an encoder as a position detection means. Normally, however, a low-cost pulse motor is driven by open-loop control. Also, closed-loop control using a pulse motor and an encoder is also available but is not popular.
Since the parameters of a conventional printer are set to guarantee the operation and specifications even in the worst environment or state, the print speed and consumption power are set to have some margins so that predetermined print quality and speed can be maintained anytime and anywhere. Among recording apparatuses that have become popular worldwide, since a recording apparatus with a stepping motor using open-loop control, which is advantageous in terms of cost, does not have any feedback control, the torque margin of the motor works under a strict condition at a certain place but with enough margin at another place. Also, recording apparatuses such as a new apparatus, used apparatus, and the like have various states. In this manner, the recording apparatus used often has an excessively large margin for the print speed and consumption power (over-specification state) depending on its use environment and state. In order to improve the performance of the recording apparatus and to attain energy savings, an appropriate margin must be maintained. As for the motor, an excessive margin leads to heat generation of the motor, and the torque characteristics also drop due to an increase in winding resistance and a decrease in coercive force.